Experimental Study On The Recovery Of Rare Earth From Low-concentration Leaching Solution Of Ion-adsorption Rare Earth Mines In The South By Ion Exchange Resin Metho

When the ion adsorption type rare earth mine production in the end,the rare earth concentration of leaching liquid will drop below 0.35 g/l,the precipitation efficiency greatly reduced,thus affect the recovery of rare earth.Aiming at this phenomenon,this research adopts the ion exchange resin method from ion adsorption type re low concentration of leaching recovery of rare earths,the purpose is to explore the suitable process conditions,improve the recovery rate of rare earth resources.This topic is studied in static and dynamic conditions by changing the different influence factors on the low concentration of rare earth leaching liquid adsorption,desorption performance changes in the test,to get the optimum process conditions eventually.The study results show that,Using ion exchange resin method from low concentration of ion adsorption type rare earth mine leaching liquid recovery of rare earth in the process is technically feasible.Under the condition of static:(1)Resin adsorption process of rare earth ions in the liquid film diffusion as the main control steps.(2)pH=4.2 and 4.5,the static adsorption capacity of the resin were 87.46 mg/g and 88.79 mg/g.(3)the hydrochloric acid and HT-6 at low concentrations of desorption effect is better,And hydrochloric acid when the concentration of 6%,Basic desorption completely on rare earth complex anion resin,HT-6 in 10%,the desorption rate reached 95%.Consider using hydrochloric acid desorption,be helpful for the regeneration of the resin and repeated recycling,so choose 6%concentration of hydrochloric acid as the desorption agent;Under the condition of dynamic ion exchange resin with low concentration of weathering crust type illuviation suitable process conditions for rare earth leaching liquid:(1)Adsorption:Velocity 10 mL/min,contact time is 4.6 min,adsorption temperature to room temperature,material liquid pH=4.25;The exchange column than height to diameter(H/D)as 14.6/2=14.31;(2)Desorption:The velocity of 6 mL/min;The adsorption contact time of 7.67 min;Temperature to room temperature;The desorption agent of 6%hydrochloric acid,dosage according to nHCl/n calculation RE=180 resin;(3)Test results:Wear leak adsorption capacity of 150.83 mL/g;Through adsorption capacity of 259.74 mL/g;Resin utilization rate of 58.07%;Desorption of desorption amount at a rate of 81.45%(t=143.90 min,C/C0=10).